An objective is to obtain a backlight in which a decrease in brightness at a peripheral portion associated with the change of viewing distance is reduced. The backlight is comprised with an optical member 107 for transforming beams projected from light sources 117A and 117B into beams having a narrow-angle light distribution in which rays having intensity of no less than a predetermined value are localized within a predetermined angle range centered in the normal direction of a display surface 106b of a liquid crystal display panel 106, and for projecting the transformed beams in the direction of the liquid crystal display panel 106; and a light distribution control member 83 for receiving the beams that are projected from the optical member 107 and that have the narrow-angle light distribution, and for projecting the received beams in the direction of the liquid crystal display panel 106, wherein a plurality of concaves 109 are provided at the light distribution control member 83 for transforming a beam, from among the beams having the narrow-angle light distribution, that enters a peripheral portion of the liquid crystal display panel 106 so that the narrow-angle light distribution of the entered beam is broadened compared to that of a beam that enters a central portion of the liquid crystal display panel 106; and curvature radiuses of the plurality of concaves are formed so that a curvature radius of a concave located at a peripheral portion of the light distribution control member 83 is smaller than a curvature radius of a concave located at a central portion of the light distribution control member 83.